Loss-in-weight feeder systems dispense materials from a hopper on a metered basis, employing feedback control based upon decreases of the weight of the material in the hopper as material is dispensed. In general, loss-in-weight feeder systems are known. Examples of such systems are described in the following U.S. Pat. Nos. 4,580,698, issued on Apr. 8, 1986, based on application Ser. No. 498,082; 4,579,252, issued on Apr. 1, 1986, based on application Ser. No. 491,708; 4,552,235, issued on Nov. 12, 1985, based on application 487,011; 4,524,886, issued on June 25, 1985, based on application Ser. No. 343,143; 4,301,510, issued on Nov. 17, 1981, based on application Ser. No. 141,343; 4,210,963, issued on July 1, 1980, based on application Ser. No. 913,203; 4,111,336, issued on Sept. 5, 1978, based on application Ser. No. 787,688; 4,111,272, issued on Sept. 5, 1978, based on application Ser. No. 748,397; 4,100,984, issued on July 18, 1978, based on application Ser. No. 702,354; 4,054,784, issued on Oct. 18, 1977, based on application Ser. No. 678,391; 3,985,266, issued on Oct. 12, 1976, based on application Ser. No. 604,506; 3,889,848, issued on June 17, 1975, based on application Ser. No. 274,844; 3,855,458, issued on Dec. 17, 1974, based on application Ser. No. 390,201; No. Re. 32,102 is a reissue of 4,320,855 issued on Mar. 23, 1982, based on application Ser. No. 125,370; No. Re. 32,101, also a reissue of 4,320,855; and No. Re. 30,967, a reissue of 3,967,758, issued on July 6, 1976, based on application Ser. No. 550,639.